Field of the Invention
The present invention relates generally to remote control model aircraft airfoil or wing building, and more particularly to a novel design and method for the inexpensive construction of an airfoil or wing or the like for incorporation into a model aircraft, with the airfoil or wing being made of a single sheet of corrugated paper board material in a manner ensuring that the airfoil or wing is both strong and durable.
Remote control model aircraft have become increasingly popular in the recent past, with the number of hobbyists increasing while the technology offers an ever-increasing diversity of different designs for model aircraft. While there is an incredibly wide variety of designs and components to choose from, ranging from simple molded foam models to complex balsa designs covered with synthetic film material, all of the designs may be categorized rather easily.
For example, all of the model aircraft fall into the categories of either fixed wing aircraft or rotating wing aircraft (helicopters). Similarly all of the model aircraft fall into the category of either gliders or powered aircraft. The present invention is concerned with fixed wing aircraft, and primarily with the design and construction of gliders, although the principles of the present invention are equally applicable to the design and construction of powered aircraft.
In order to overcome the force of gravity exerted by the Earth to enable a model aircraft to remain in the air, the aircraft must be acted upon by a lift force. This lift force is generated by air flowing over the surface of an airfoil, which draws on the principle of Bernoulli's law. The cross-section of the airfoil is designed so that the angle at which the airfoil is presented to the air causes the air to flow more swiftly over the upper surface of the airfoil than it does over the lower surface of the airfoil. As a result of this velocity differential, air pressure is lower above the airfoil than it is below the airfoil, which results in a lift force which urges the airfoil upwardly.
Fixed wing model aircraft utilize one or more airfoils to provide the lift force which enables the aircraft to fly. The primary airfoil which produces the most lift in a model aircraft, like a real aircraft, is the wing of the aircraft. Model aircraft wings may be either straight or swept back, and may be either only a portion of the model aircraft or substantially the entire model aircraft (essentially a flying wing). The model aircraft remains in flight whenever the lift force equals or exceeds the total weight of the model aircraft.
As might be expected, there exists a considerable variety in wing designs for fixed wing model aircraft. However, only a few construction methods are widely used for the construction of model aircraft wings. The more inexpensive method is molded foam construction, which results in a light weight wing of clean, smooth construction. While such foam wings are moderately priced, they are unfortunately not highly durable. In addition, some foam materials tend to melt in the presence of fuel or like liquids.
The most popular construction technique is the balsa frame which is built up and covered with a thin synthetic film. The balsa frame consists of spars extending the width of the wing, with ribs being used to hold the spars in place. The frame is quite complex of construction, and is thus labor intensive. The completed wing frame is covered with the thin synthetic material, which is adhesively secured and/or heat shrunk onto the wing.
It will at once be appreciated by those skilled in the art that such wings are the most desirable, since they are fairly strong and light weight. In addition, a wide variety of different wing constructions may be made by utilizing this process. Prebuilt wings used on almost-ready-to-fly (ARF) model aircraft are some of the nicest available, but they tend to be rather expensive to purchase. The wings may be built by the hobbyist, but they are extremely labor intensive and can require days or even weeks of work to build a single wing.
It is accordingly the primary objective of the present invention that it provide an improved model aircraft wing design and method for construction of the model aircraft wing which is not so highly labor intensive as the balsa and thin film construction. It is a further objective of the present invention that it utilize materials which are both easy to work with and readily available, thereby opening the hobby of remote control model aircraft to the widest segment of the population possible. In addition, the method of construction utilized by the model aircraft wing of the present invention should be relatively simple so as not to preclude inexperienced hobbyists from practicing the present invention.
It is a further objective of the present invention that it enable the construction of a widely diverse number of different wing and aircraft designs. It is a related objective of the present invention that it enable the construction of sophisticated wing designs, including multi-angle designs such as straight wings with polyhedral surfaces. The improved wing design of the present invention should additionally be adaptable to allow for mass production of prefabricated, unassembled wing and model aircraft components.
The apparatus of the present invention must also be of construction which results in assembled wings and model aircraft which are both durable and long lasting, and which allow considerable abuse while requiring little or no rebuilding or rework to be provided by the user. In order to enhance the market appeal of the apparatus and method of the present invention, they should also advantageously utilize the most inexpensive materials available to thereby afford it the broadest possible market. Finally, it is also an objective that all of the aforesaid advantages and objectives of the present invention be achieved without incurring any substantial relative disadvantage.